automatic buck-boost dc-dc converter lithium battery charging module with an adjustable constant current / constant voltage output. input range 5-30 V DC and efficiency up to 95%. Suitable for a variety of applications. who it's for electronics enthusiasts, manufacturers, and technicians who require precise regulation for models, solar systems, or power banks. construction and accuracy abs+aluminium housing withstands workshop conditions while maintaining voltage accuracy of 0.01 V across full-load ranges. design and protection wide input voltage compatibility (5-30 V DC); integrated protections for over-voltage, over-current, and over-temperature; led indicators for real-time monitoring. use scenarios - precise charging for model builds, hobby electronics, and small scale projects that need cc/cv control - solar charging systems and portable solar setups with lithium batteries - power banks and lithium packs requiring reliable cc/cv regulation during charging